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Branch point in a polymer. Polymer architecture in polymer science relates to the way branching leads to a deviation from a strictly linear polymer chain. [1] Branching may occur randomly or reactions may be designed so that specific architectures are targeted. [1] It is an important microstructural feature.
In polymer science, the polymer chain or simply backbone of a polymer is the main chain of a polymer. Polymers are often classified according to the elements in the main chains. The character of the backbone, i.e. its flexibility, determines the properties of the polymer (such as the glass transition temperature).
An important microstructural feature of a polymer is its architecture and shape, which relates to the way branch points lead to a deviation from a simple linear chain. [25] A branched polymer molecule is composed of a main chain with one or more substituent side chains or branches.
In polymer chemistry, branching is the regular or irregular attachment of side chains to a polymer's backbone chain. It occurs by the replacement of a substituent (e.g. a hydrogen atom ) on a monomer subunit by another covalently-bonded chain of that polymer; or, in the case of a graft copolymer , by a chain of another type.
The steady-state concentration of the growing polymer chains is 10 −7 M by order of magnitude, and the average life time of an individual polymer radical before termination is about 5–10 s. A drawback of the conventional radical polymerization is the limited control of chain architecture, molecular weight distribution, and composition.
Chain-growth includes both initiation and propagation steps (at least), and the propagation of chain-growth polymers proceeds by the addition of monomers to a growing polymer with an active centre. In contrast step-growth polymerization involves only one type of step, and macromolecules can grow by reaction steps between any two molecular ...
An ideal chain (or freely-jointed chain) is the simplest model in polymer chemistry to describe polymers, such as nucleic acids and proteins.It assumes that the monomers in a polymer are located at the steps of a hypothetical random walker that does not remember its previous steps.
CW can be also considered as a specific case of intermolecular chain transfer (analogous to radical ethene polymerization). This reaction gives rise to branched and hyperbranched/dendritic hydrocarbon polymers. This process is also characterized by accurate control of polymer architecture and topology. [1]